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On Renewable Energy Provides 100 Percent of New Electrical Generation in July

Just to put this sensationalist headline into perspective:

The energy infrastructure update reports 699 MW of wind and 1131 MW of solar coming online in the first half of 2014. If we assume that, due to capacity factor considerations, wind capacity generates about half of conventional capacity per MW and solar capacity generates about a third of conventional capacity per MW, we can estimate that wind and solar displaced about 727 MW of conventional generation in the first half of the year (assuming stagnant demand).

Considering that the US has 1161720 MW of (mostly conventional) capacity, it can be estimated that wind and solar will need 800 years to displace all conventional generation at this rate of deployment. It should also be noted that both wind and solar deployment rates are down from H1 2013. 

August 29, 2014    View Comment    

On Seeking Consensus on the Internalized Costs of Energy Storage Via Synfuels

DATA: P2G2P breakeven spread: $330/MWh. This is for a capacity factor of 20% (to buy electricity at a low cost of $20/MWh) and capital costs of $6000/kW for H2 (P2G + H2 storage + G2P) or $5000/kW for CH4 (P2G + methanation). 

August 13, 2014    View Comment    

On Seeking Consensus on the Internalized Costs of Energy Storage Via Synfuels

DATA: P2F cost: $35/MMBtu or $202/boe. This is based on a capacity factor of 40% and capital costs of $2500/kW (P2G + methanation). Capital costs are half that of P2G2P because the process is roughly twice as afficient. It is assumed that a relatively cheap source of concentrated CO2 is available. 

August 13, 2014    View Comment    

On Can Nuclear Make a Substantial Near-Term Contribution?

Interesting point. Although I don't think it can be disputed that energy growth is highly correlated with economic growth since the start of the industrial revolution, there are many countries which can no longer grow effectively by simply scaling up material consumption (and energy use). In fact, I believe that, for most of the developed world, further increases in material and energy consumption are neither economic nor desirable. A conscious move away from consumerism and towards various avenues of non-material development would appear to be highly beneficial in this case. Unfortunately, our debt-based monetary system makes it very difficult to move away from the consumerist growth model. 

For most of the developing world, however, disposible income remains about an order of magnitude below developed world standards. Most of these 6 billion (and counting) people can still benefit greatly from larger living quarters, more public infrastructure, more home appliances, personal transportation etc. - all material things that require substantial energy inputs both under construction and operation. 

When it comes to driving this material growth, coal is often the primary source. Despite its environmental drawbacks, coal is, in the majority of cases, locally available in abundance to drive economic growth (only something like 10% of coal is traded internationally). This feature of coal combined with its simplicity and versatility explains why nations almost exclusively start their economic development with coal as pointed out in my previous article

Energy constraints are mostly related to oil - something for which we do not yet have any truly scalable substitutes. Here I completely agree with you that energy efficiency is paramount to ensuring economic growth. 

August 8, 2014    View Comment    

On Can Nuclear Make a Substantial Near-Term Contribution?

Just to reiterate: I am assessing the maximum potential growth rate of technologies that can fuel rapid developing world growth (note that the developing world is projected to be responsible for the vast majority of global energy growth over coming decades). It is clear from the above analysis that fossil fuels, especially coal, remain the best driver of growth by a long shot. If nuclear and wind/solar are to take over from fossil fuels as the primary growth driver in the developing world, scaling rates will have to increase dramatically and the political constraints currently holding nuclear back on a global scale (neglected in my simple scaling estimation) will have to be greatly reduced. The data provided in this article shows that, under the assumptions given, my initial estimate is fairly accurate in a country where political constraints on nuclear are quite low. 

BTW, have you found a good explanation for the discrepancy between the empirical data in the Wiser's report I referred to in the last comment of our discussion here and your usage of a 40% capacity factor as a representative number for global statements about wind energy? For ease of reference, the particular statement is "Somewhat surprisingly, however, given the significant scaling in turbine design over the years, average 2012 capacity factors do not show an increasing trend among post 2005 project vintages." (statement related to Figure 28 in this report showing average capacity factors of about 31%). It should also be considered that the US has some of the best wind resources in the world and achieves capacity factors of about 34% above the global average. 

August 7, 2014    View Comment    

On Why we Need CCS - Part 5: Bridge to a Sustainable Energy Future

I would highly recommend checking out this entire CCS series to get my full argument about why we need CCS. 

The full lifecycle emissions of CCS is about 20% of an unabated plant, so, even with the energy penalty, including CCS can achieve large emission reductions.

About storage, ocean storage will be the last option to be utilized. First will be EOR oil fields where CCS could even be profitable if scaled up, second will be depleted oil fields where infrastructure already exists to bring down costs and third will be saline aquifirs where huge volumes of CO2 can be permanently stored at very low risk of leakage. 

August 7, 2014    View Comment    

On Can Nuclear Make a Substantial Near-Term Contribution?

Thanks Nathan. However, I still think that the capital costs of a given technology offers a better indication of the maximum scaling rate, rather than the overall economics (LCOE). The analysis in this article offers some support to this notion. It should be added, however, that a technology will never reach its maximum scaling rate if overall economics are not competitive.

About coal in China, there is now lots of activity to shift coal consumption away from population centres in order to reduce air pollution. I'm sure you are aware of China's enormous SNG plans, but there are also plans to build enormous coal plants at large, remote mines and transmit the power to population centres through HVDC cables. This article gives an example of a truly monstrous 9.34 GW plant being built next to a coal mine in the Gobi desert. Coal is currently constrained by air pollution in China, but if these plans remove this constraint, things could become very bad for the climate...

Thanks for the deeper insight into the Chinese nuclear expansion. Do you have some figures about costs and build times of Gen III reactors relative to Gen II? Do you expect the trend in post Fukushima reactor starts to accelerate soon?

August 4, 2014    View Comment    

On Can Nuclear Make a Substantial Near-Term Contribution?

Good comment about hydro. What is your opinion on the potential of using hydro for balacing intermittent renewables? At first glance, it appears very good because, as you said, potential energy can simply be deferred for later use (solar/wind troughs). But using hydro for balancing large amounts of intermittent renewables will also have some economic ramifications. 

The scaling of the turbine relative to the reservoir size is presumably done to ensure adequate utilization of water resources in the rainy season. The stongly seasonal nature of hydropower then causes relatively low capacity factors due to lower flows in the off-peak season. For example, the average monthly US hydro generation varies almost by a factor of two over the year and it can be assumed that generation profiles for individual dams over shorter timescales vary substantially more. 

When large amounts of wind/solar require balancing, it will necessitate spillage during rainy months as hydro is deferred during a time when the turbines would otherwise be running at full capacity. More wind/solar balancing will therefore either require costly oversizing of turbines or costly spillage of potential energy. I wonder whether modern hydro dams are built with wind/solar in mind or still only to maximize yearly production at minimum capital costs. 

August 1, 2014    View Comment    

On Why we Need CCS - Part 5: Bridge to a Sustainable Energy Future

Thanks for spreading the word. I must say, I was pleasantly surprised by the critical nature of the discussion that developed below the Cleantechnica article. Given the clear technology preferences of Cleantechnica, this is very encouraging. Seems like the "myth" is quite some distance from being put to bed. Some more mythbusting awaits here

BTW, your reference to TEC as an "echo chamber" for nuclear over renewables is unfounded. If you look at the article profile on TEC, you will notice a good balance between technologies. In contrast, sites like Cleantechnica and Reneweconomy can be more accurately described as "echo chambers" because the vast majority of articles give positive press to a predetermined technology class, allowing advocates of these technologies to consistently reinforce each others' beliefs without too much opposition. This is not possible within the technology-neutral environment on TEC. Thus, if you want some truly critical discussions of your ideas, I would strongly encourage publishing some material on TEC. 

Also, my article does not say that only nuclear can scale to prevent global warming and wind energy should be ignored. It simply states that both nuclear and wind scale much more slowly than fossil fuels (hence the need for retroactive CCS described earlier in the series), with wind/solar (in a technology-neutral environment) being even slower than nuclear based on simple LCOE and LACE considerations.

August 1, 2014    View Comment    

On Can Nuclear Make a Substantial Near-Term Contribution?

Yes, as shown in the graph, Fukushima had a very large negative impact on the near-term prospects (up to 2020) of Chinese nuclear. However, such black swan events generally happen only once every few decades, implying that nuclear starts may well accelerate in the next decade similarly to the pre-Fukushima years. As you said, regulation will play a major role, but I think the Chinese will be sufficiently desparate for reliable, emissions-free power to provide a good nuclear growth environment. 

About the increasing generation gap between wind and nuclear, this gap should close over the next 2-3 years as the large number of nuclear plants started in the 2008-2011 period are completed. Let's wait and see...

China is going for a lot of rooftop solar this year, implying that they will trade low capacity factors and high installation costs for easier integration. Unfortutely, solar irradiation in the south-eastern population centres of China is pretty lousy, implying that a similar capacity expansion to wind (albeit substantially more expensive) will generate much less electricity. 

About hydro, it is important to keep in mind that, on a per-capita basis, China is a very dry country. Hydro has been expanding impressively over the past couple of years and also into 2014, but may well fall behind total energy growth in the future. The very large energy demand pressures and enormous scale of Chinese hydro facilities will also make it difficult to operate as wind/solar backup. 

Thanks for the interesting link to Chinese wind power locations. However, the map gives a bit of a distorted impression due to the very large number of planned offshore wind farms included. I have my doubts about how much of this will be realized simply because offshore wind is so expensive and has actually been getting more expensive over time. More detailed information on the challenges faced by Chinese wind expansion can be found in Michael Davidson's excellent East Winds column on TEC. 

About the recurring argument that wind/solar costs will continue declining, I'm still of the opinion that integration challenges (profile, balancing and grid-related costs) and other factors will overwhelm even large cost declines at moderate penetrations (~10-50% of electricity or 4-20% of total energy depending on location). We will probably not agree on this, but, similarly our different views on climate change, we will just have to accept each other's different perspectives. 

August 1, 2014    View Comment    

On Can Nuclear Make a Substantial Near-Term Contribution?

Thanks Paul. This is a very good point. I will include it in the article sometime later today with an additional graph to show the potential CO2 abatement between wind and nuclear. Do you think it will be a reasonable assumption to say that nuclear abates about twice as much CO2 per kWh generated because it primarily displaces baseload coal while wind primarily displaces load-following gas/hydro?

August 1, 2014    View Comment    

On Can Nuclear Make a Substantial Near-Term Contribution?

Thanks Jesse. Yes, I really do think this is the core of the matter. Even in 2013, a year of worryingly low developing world economic growth (thus low energy growth), non-hydro renewables contributed only 7.5% of the increase in energy consumption. Nuclear provided 3.6% of the increase. In more normal growth years (such as 2011 and 2012), these percentages are halved. (Observations based on BP data.) 

Yes, deployment rates will increase, but it will most probably be decades (if ever) before deployment rates increase by an order of magnitude and, until that time, fossil fuel combustion, coal in particular, will have to keep on increasing. This is clearly in conflict with the 450 ppm scenario. It is important that we openly discuss this objective reality, regardless of how inconvenient it might be. 

July 31, 2014    View Comment